Bree Street’s Portside gets five-star rating

First high-rise office development in South Africa to achieve top score

PORTSIDE, the new high rise under construction in Bree Street, has received a five-star Green Star Office Design Rating by the Green Buildi n g Council o f S o u t h Af r i c a (GBCSA).

Portside is jointly owned by Old Mutual Properties and FirstRand and consists of 57 000m of AAAgrade space over 20 office floors, with retail space at street level on the lower and upper ground floors. In addition, there are three basement parking levels, a further seven structured parking floors in the podium and two plant floors at roof level, making 34 floors in total.

“This acknowledgement makes Portside the first five-star Green Star SA- certified high- rise office development in South Africa. The design is sensitive to the environmental and aesthetic requirements of the building,” says Derick Henstra, executive chairman of dhk Architects, who designed Portside in a joint venture with Louis Karol Architects.

“Initially the project aimed at a four-star rating, but the client saw the opportunity to raise the bar for this AAA-grade commercial development in the Cape Town CBD. One of the real benefits of pursuing Green St a r i s t he i nt e g r a t e d approach to design challenges,” says Mike Munnik of Afama, the sustainability consultancy on the project.

“Problems were resolved as a design team rather than as individual disciplines.

“This contributed enormously to the successful outcome.”

Portside has focused on the environmental initiatives associated with GBCSA projects, including energy reduction through an efficient air-conditioning system; the capturing, storage and reuse of rainwater, as well as grey water for use in toilets, which reduces potable water use; the use of low-embodied energy materials such as recycled reinforcing steel and cement replacement

‘The energy use is minimised for all areas, including parking levels, and ultimately eliminated when unoccupied’

with industrial waste products; and the maximisation of natural light through the provision of a highquality double-glazed façade.

Steve Peters, the dhk director responsible for Portside, says a particular design challenge was balancing the vast double-glazed curtain wall façade with the mechanical and electrical services necessary to maintain high occupant comfort.

“One of the main distinguishing features and innovations in Portside includes the application of LED light fittings throughout the office space. This significantly lowers the energy consumption and is a first for any office building in South Africa,” says Munnik.

“Furthermore, the energy use is minimised for all areas, including parking levels, and ultimately eliminated when they are unoccupied through the provision of movement sensors. In addition, the façade has been designed for total disassembly as each component of the unitised façade panels was marked in accordance with a disassembly plan, which identifies the sequence of removing each panel for recycling or later reuse on another building. This is also understood to be a first for a tall building in South Africa.”

Other green features include a series of electric car charging vending points, with infrastructure for additional points at a later stage, to allow for onsite recharging of electric cars while owners are at work.

In addition to the 227 bicycle racks for staff and visitors, a number of community bicycle racks have been provided on the pavement at street level to encourage alternative means of transport for businesspeople, personal use, tourists and couriers in the lower CBD. This is in support of the City of Cape Town’s non-motorised transport strategy and Ride Your City initiative.